The police officer who fatally shot an unarmed black teenager in Ferguson, Missouri has been identified as Darren Wilson. The incident, which happened on August 9, stoked racial tension throughout the country.

Michael Brown was shot dead while walking to his grandmother’s house after getting into an argument with the law enforcement officer in Ferguson, a suburb of St. Louis. The statement identifying Wilson as the shooter was made by Ferguson police chief Thomas Jackson, standing in front of the convenience store that was burned down during four nights of demonstrations and rioting.

Police chief Jackson had resisted calls to name the officer in question for four days, citing threats that had been issued on social media. He gave no details regarding the number of bullets that had been used to kill the teenager. Protesters had demanded to know the name of the officer responsible for killing the 18-year-old.

Local authorities said they will work to ensure that Wilson is kept safe, Missouri Governor Jay Nixon said Friday. Wilson, a six-year veteran on the Ferguson police force, had a good record, Jackson said at a news conference.

Jackson also added that a burglary had been reported in the area where Brown was shot. The deadly interaction was swift: the police chief said Wilson encountered Brown at 12:01 am and had shot him by 12:04 am, Reuters reports.

However, only later in the day police announced that Officer Wilson was unaware of the robbery incident. Brown and his friend were stopped before shots were fired, Chief Jackson said, "because they were walking down the middle of the street blocking traffic."

Vigils were held in 90 cities across the country in memory of the teenager, according to AP, while a protest in Ferguson on Wednesday turned violent after police turned against the crowd, deploying tear gas against them.

“This is no longer a peaceful assembly. Go home or be subject to arrest,” police warned through a bullhorn, shortly before shooting tear gas at the protesters. Prior to that, officers were telling people to stay away from the vans.

Police also shot rubber bullets, and smoke grenades and tear gas canisters were fired into the crowd and the surrounding neighborhood. In response, some of the protesters reportedly threw rocks and bottles at the police.

Despite 65 percent of Ferguson’s 21,000 population being black, all but three out of the 53 police officers in the area are white.